Improvement in telegraph transmitters



D. HERMANN. Telegraph Transmitters.

Patented Dec. 16,1873.

i in diam AM PHaI'U-UTHMMPH/l' 610. M l fassannz's mums) UNITED STATESPATENT OFFICE.

DAVIS HEBMANN, OF NEW YORK, ASSIGNOR TO CHARLES H. SMITH, OF

-' BROOKLYN, N. Y.

IMPROVEMENT IN TE LEGRAPH TRANSMITTERS.

Specification forming part of Letters Patent No. 145,567, dated December16, 1873 application filed September 24, 1872.

To all whom it may concern:

Be it known that I, DAVIS HERMANN, of the city, county, and State of NewYork, have invented an Improvement in Transmitting Telegraph-Instrument,of which the following is a specification:

This instriunent is made for transmitting pulsations to produce dots anddashes at the receiving-station similar to those in the Morse alphabet;but, instead. of one finger-key operated by an experienced person, theinstrument is automatic, and the proper pulsations are sent from arevolving cylinder through a spring that is acted upon by one of thekeys in a range of keys, each of which is marked with the number orletter to be transmitted by it. This cylinder is coated withnon-conducting material, in which are openings for the contact-spring toreach the metal of the cylinder.

The cylinder is revolved by clock-work, and a small magnet is providedthat is placed in the main line, so that by its sound the operator mayknow that his own message is being sent, or may refrain from sending anymessage until the line is clear.

This telegraph is particularly available between dwellings and a centralstation as a means of calling attention or communicating intelligence,and can be used by an inexperienced person. i

In the drawing, Figure 1 is a plan of the instrument, and Fig. 2 is avertical section transversely of the cylinder. The cylinder at issustained by the frames b b, and connected with the clock-work or trainof gearing driven by the spring in the barrel (1,- and c is a fly orgovernor to regulate the speed of the train of gearing.

The finger-keys f are more or less in number, according to whether theinstrument is to be employed for sending letters or for numbers in acode of signals-generally the latter. These keys move upon the shaft orbar g, and the extent of motion is determined by the longitudinal stopsor bars 71. The keys are drawn back to a normal position by means ofthesprings Z, and each key is provided with a spring, 2, that is made tobear upon the surface of the cylinder at when the key with which it isconnected is depressed. These springs t are relieved by the inclined endof the key f passing away from an incline upon the spring when the keyis depressed, thereby allowing the spring to press with its own poweronly against the surface of the cylinder a.

This cylinder a is made of metal, with a surface of non-conductingmaterial or varnish upon the said cylinder at, and through thisnon-conducting coating there are openings made to lay bare the metal ofthe cylinder,

and these openings are of a character to represent dots and dashes, andgrouped to form characters corresponding with those representin g thenumber or letter of the particular key.

One wire of the telegraph-line is connected with the range of springs;the other goes through the magnet n, and then is connected with themetallic frame.

When any pulsation is being sent over the line, all the magnets nrespond, and their armatures click and indicate by sound that the lineis in use. As soon as there is no sound, the line is in condition foruse by any other person.

When the instrument is to be used, the lever R- is depressed thatseparates the stop-pin s, unlocking the cylinder a, so that it revolves.The desired key of the range of finger-keys f is depressed, and, as thecylinder a revolves, the proper pulsations for a Morse or otherreceiving-instrument are made by the contact of the spring 2' with themetal of the cylinder through the openings of the non-conductingsubstance, and that material breaks the cir cuit to produce the separatepulsations, and at the end of the revolution of the cylinder at thestops 8 again lock the same, and the spring is moved from contact uponrelieving the finger-key.

I am aware that a cylinder has been made with metallic projectionssurrounded by a surface of non-conducting material. This is expensive.By my device the cost is lessened;

and the cylinder is not liable to injury, be i revolving metal cylinderat, having a non-eoncause the keys do not press upon the surface;ducting surface, with openings through the they only relieve the springsthat act with same, as and for the purposes set forth. their own regularpressure, which is very Signed by me this 5th day of August, A. D.slight. 1872. I claim as my invention DAVIS HEEMANN. The springs i,pressed back by the inclined lVitnesses: ends of the keys f, but allowedto move when GEO. T. PINGKNEY, the key is depressed, in combination withthe CHAS. E. SMITH.

